1. Field of the Invention
The present invention relates to a cationic keratin derivative, a process of its preparation and hair treating cosmetics containing it.
2. Description of the Prior Art
Hair is one of the most important portions for beauty care, and various beauty treatments are applied thereto, in which a variety of hair treating cosmetics are used. In this specification, the term "hair treating cosmetics" is used to generally represent all cosmetics applied to hair, including, for example, shampoos, hair rinsing compositions, pre-shampoo conditioners, after-shampoo conditioners, setting lotions, blow-styling lotions, hair sprays, hair dyes, bleaches, permanent wave primary agents, permanent wave oxidizing agents, hair coloring agents, and hair dressing agents such as hair liquids or hair tonics.
Conventional hair treating cosmetics are not completely satisfactory for one reason or another.
For instance, shampoos are intended to remove dirt deposited on hair, or dirt comprising decomposition products or oxides of the sebum secreted from a head skin, and their basic materials are anionic surfactants, nonionic surfactants or amphoteric surfactants. When hair is washed with shampoos containing these materials, the sebum or other oil components on the surface thereof can be excessively washed off, and the texture of hair after the washing tends to be bad, and it becomes difficult to comb or brush the hair. Further, when dried completely, the hairs tend to be hard to style. Especially in winter when humidity is low, brushing is likely to cause static electricity, which in turn causes fly-away. Hairs will thereby be tangled with one another, and become harder to comb, leading to split-ends and broken hairs.
In order to eliminate such drawbacks, it is known to incorporate oils or the like to usual shampoos so that an oil is supplemented at the time of washing hair. Various oil agents are incorporated in usual shampoos.
However, in a shampoo composition system, the entire system is maintained in an emulsified or dissolved state by a surfactant, and it has been difficult to incorporate an oil in an adequate amount for scale and hair without impairing the stability of the system.
If a substantial amount of an oil agent is incorporated, the amount of the oil adsorbed on the hair increases. However, there used to be drawbacks that the essential functions of the shampoo, such as foaming property and detergency were thereby considerably degraded, or a commercial value of the shampoo was thereby impaired.
On the other hand, there have recently proposed various shampoo compositions containing cationic polymers for the purposes of imparting a rinsing effect to the hair after washing. However, these compositions had drawbacks that (1) although they were effective for conditioning, they were inferior in foaming property and detergency, (2) they tended to be colored or underwent color change with time, (3) although they were superior in the foaming property, they were inferior in the conditioning effect, or (4) they were costly.
A hair rinse composition is designed to be used for the purposes of preventing a loss of flexibility, luster, and combing easiness of hair and a tendency for damage, split-ends or broken hairs, and providing hair conditioning effects, i.e. imparting flexibility, softness and smoothness to hair and improving combing easiness. It is composed of a quaternary ammonium salt as a cationic surfactant, and an oil component such as a liquid paraffin or a higher alcohol.
However, the quaternary ammonium salt does not have sufficient ability to emulsify or disperse an adequately effective amount of oil component in a stabilized condition, and the system was unstable. If a nonionic surfactant was incorporated to overcome the difficulty, the essential rinsing effect was degraded. Under the circumstances, there has been proposed to incorporate, instead of the above mentioned oil components, other compounds such as an anionic surfactant, an anionic polymer compound, a cationic polymer compound, or a hydrolyzed product of collagen, to obtain a stable hair rinsing composition. However, no satisfactory result has not yet been obtained.
Hair setting compositions such as a setting lotion or a hair spray, are used for the purposes of preventing loosening of set hair due to a high humidity or wind. Conventional hair setting compositions contain a resin component such as an acrylate-methacrylate co-polymer or a polyvinylpyrrolidone-vinylacetate co-polymer as a fixing agent to provide a setting effectiveness.
However, such a resin component has a poor washability, and is hardly removable completely from hair even when the hair is washed with a shampoo. Accordingly, it is likely to remain on the surface of the hair and causes undesirable phenomena such as an increase of the frictional coefficient of the hair, formation of split ends or broken hairs by brushing, and deterioration of the texture of the hair.
In order to eliminate such drawbacks, there has been an attempt to incorporate a nonionic surfactant, a wetting agent, etc. into the resin component thereby to increase the water solubility. However, this method has a drawback that the setting power under a high humidity condition will thereby be degraded and the essential property of the hair setting composition is thus lost, although the washability is thereby improved.
Pre-shampoo conditioners are designed to be applied prior to hair washing, followed by normal hair washing, and to prevent damages of the hair at the time of the washing, the rinsing, or the finishing of the hair e.g. by drying the hair with a drier and thus to impart the conditioning effects to the hair. Presently, pre-shampoo conditioners containing fats and oils such as lanolin as the major component are commercially available and favourably used. However, when hair is subjected to protecting treatment with a pre-shampoo treatment of a type containing fats and oils as the major component, the finished hair tends to be greasy and often gives rise to a drawback that the hair becomes sticky, and a further study for improvements is desired.
Permanent wave waving lotion and neutralizer are designed to set the waves of hair by reducing followed by oxidizing the hair and to be used for a permanent wave method. The permanent wave waving lotion comprise a reducing agent such as thioglycollic acid or cystein to reduce the disulfide bond (--S--S--) in the hair into hydroxysulfide an alkaline substance as the major components. Whereas, the permanent wave neutralizer comprise an oxidizing agent such as a bromate, a perborate or an aqueous hydrogen peroxide solution to oxdize S--H into disulfide bonds as the major component.
However, according to such a permanent wave method using the permanent wave waving lotion and neutralizer, the hair is subjected to severe conditions such as oxidation and reduction, and undesirable phenomena such as a decrease of the strength of the hair and a degradation of the texture of the hair occur. Such hair can hardly be combed and is likely to be hitched and damaged by peeling off of the cuticle of the hair, splitting or breakage.
The degradation of the hair by the permanent wave waving lotion is caused by the breakage of keratin constituting the hair, by the action of the permanent wave waving lotion, and consequential dissolution of proteins or amino acids. Accordingly, in order to prevent the degradation, it is necessary to supplement the thus lost protein components.
Therefore, there has hitherto been an attempt to incorporate into the waving lotion a hydrolyzed product of collagen. However, such a hydrolyzed product is likely to easily be washed off by the rinsing or washing of the hair after the cold wave treatment, and therefore, no adequate effect was obtainable.
On the other hand, the degradation of the hair by the permanent wave neutralizer is caused by the swelling of the hair by the permanent wave waving lotion, followed by the action of the neutralizer to damage the hair. In order to prevent such damages, it has been proposed to incorporate an oil agent or a wetting agent. However, none has yet been proved to be satisfactory.
Hair dyes, bleaches and hair coloring agents are intended to be used for the purpose of dyeing white hair with a black color, making up or harmonizing the hair color with the clothes. They are generally classified into those wherein oxidation colors are used, those wherein decolorizing agents are used, those wherein the dyeing is carried out by solvent assistants with use of oxidation colors, those wherein hair coloring agents are used, and those wherein iron-pyrogallol is used.
Among these, the oxidation hair dye agents are designed to have an oxidation dye intermediate of a low molecular weight penetrated into the hair and have it oxidation-polymerized within the hair to form a color for hair coloring. The bleaches are designed to oxidatively decompose melamine by an alkaline hydrogen peroxide, thereby to decolorizing and dyeing the hair. However, these coloring agents bring about chemical changes of the hair and thus, the hair is heavily damaged. Further, in the case of hair dye agents wherein oxidation colors or pigments are used (i.e. temporary hair dyes), a coloring agent merely deposits on the hair and it is likely to be removed by e.g. washing the hair. Therefore, it is necessary to repeatedly carry out the hair dyeing treatment at certain intervals. However, in doing so, the hair dyes are accumulated on the hair and tend to give damages to the surface of the hair. Furthermore, it is common to incorporate a polymer resin as a binder into a hair dye, and if such a resin remains on the hair, the hair becomes to be hardly combed or brushed and is likely to be damaged by the combing or brushing.
In order to prevent such damages to the hair, it is common to incorporate an oil agent or a wetting agent into the hair dyes. However, the effectiveness is merely temporary and inadequate, and a further improvement is desired.
On the other hand, keratin which is a fibrous protein distributed over the outer skin of a higher animal and having a function of protecting a living body, is composed of 18 different kinds of amino acids (i.e. alanine, alginine, aspartic acid, cystine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophane, tyrosine, and valine), has a high cystine content and is characterized by a cross-linked structure having one disulfide bond (--S--S) per an average of from 10 to 20 amino acid residues.
Keratin is widely distributed in hair, nails, wools, feathers, horns, etc. Especially, it constitutes the major components of hair and nails, and is therefore believed to have good affinity to hair and skin. Accordingly, a study has been made on the incorporation of such keratin into cosmetics. However, keratin per se is insoluble in a usual solvent, and practically, the range of its application is very much limited.
In order to use keratin for e.g. cosmetics, it is firstly necessary to dissolve it in a certain solvent, e.g. in water. To do this, it is necessary to split the cross-linked disulfide bond. The splitting may be done either by reduction or by oxidation. By the reduction, the disulfide bond is converted to a sulfhydryl group (--SH) and the reduction product is called keratin. On the other hand, by the oxidation, the disulfide bond is converted to a sulfonic acid group (--SO.sub.3 H), and the oxidation product is called keratose. The straight chain proteins thereby obtained should essentially be water soluble. However, due to the hydrogen bond, ion bond, hydrophobic bond, etc. between the proteins themselves, they are hardly soluble in water or in an organic solvent, and, if dissolved, they give only a very dilute solution.